WACO, Texas — Baylor senior quarterback Seth Russell will undergo surgery to his fractured left ankle and miss the remainder of the 2016 regular season.

“Seth worked so hard to come back from the neck injury, and it’s not about losing the talent and production at quarterback, it’s more just like having one of your own children hurt,” acting head coach Jim Grobe said. “It breaks your heart to see a really, really good guy get hurt like that. Just really, really sad because you love the kid so much.”

Russell was injured in the third quarter of Baylor’s loss at No. 9 Oklahoma Saturday. The ankle injury comes just over a year after the Garland, Texas, product suffered a neck injury on Oct. 24, 2015, against Iowa State. Russell had surgery for that injury as well, missing the remainder of the 2015 season. He returned to action in 2016 and had piloted the Bears to a 6-3 record.

In 2016, Russell had thrown for 2,126 yards and 20 touchdowns, while completing 54.7 percent of his passes (152-of-278) with eight interceptions. The senior had also racked up 506 rushing yards on 94 carries with eight scores. Nationally, Russell ranked 10th with 18.9 points responsible for per game, 15th in passing yards per completion (13.99), 23rd in total offense (292.4) and 30th in passing TDs (20).

As a starter at Baylor, Russell owned a 14-3 record, throwing 54 TD passes and only 14 interceptions in those games. For his career, the veteran signal caller ranks second in school history in passing efficiency (159.36). He is also third in the BU record books with 60 career TD passes and seventh in passing yards (5,461). Russell holds the school record for yards per play in total offense with an average of 8.324.

Russell had also helped Baylor rise to a program-best ranking of No. 2 in both the AP Top 25 and the Amway Coaches Poll in 2015. He was named a semifinalist for the Davey O’Brien award last season and was a 2016 watch list member for the Maxwell Award, Wuerffel Trophy, Davey O’Brien Award, Walter Camp Award, Johnny Unitas Golden Arm Award, Manning Award, Earl Campbell Tyler Rose Award, Senior Bowl and Rotary Lombardi Award.

Moving forward, Baylor’s first-string quarterback will be Zach Smith, a true freshman from Grandview, Texas, who has appeared in six games for the Bears. Smith owns a 129.85 passer efficiency rating, having thrown for 272 yards and two TDs on 16-of-35 passes.

Baylor will now host Kansas State at 11 a.m. Saturday at McLane Stadium. That game will be televised on ESPN2 and serve as Senior Day for the Bears.